print $cgi->start_form({-id=>'form1',-name=>'form1',-action => "$url/cgi-bin/passwd/ssh.pl", -method=>'post'});
[...]
 while ($prepare_select_hosts->fetch()){

        print $cgi->Tr(
                        $cgi->td({-width=>'20'},$id),
                        $cgi->td($hostname),
                        $cgi->td($ip),
                        $cgi->td($cgi->checkbox(-name=>'host', -value=>"$ip"))
                );
        }
        
        print $cgi->Tr($cgi->td(
                $cgi->button(-name=>'checkall',
                             -value=>'Check All',
                             -onClick=>"AllMessages(this.form);"));